The invention relates generally to computer systems, and deals more particularly with a technique to back-up a computer program.
There are various types of computer programs today, such as operating systems, middleware and applications. A middleware program acts as an interface between two applications (typically on other servers) to facilitate communication of data between the two servers. Middleware assists the communication when the two applications have different communication protocols or are otherwise not suited for direct communication with each other. One example of middleware is IBM MQ Series (which is also known as IBM Websphere MQ) program which establishes an asynchronous message-queuing service to enable communication of messages between two or more other applications which differ in type from each other. The IBM MQ Series/Websphere MQ program manages the I/O to these other applications, establishes message queues, manages authorizations to the message queues, and maintains configuration files and user exits. The authorizations indicate which applications are authorized to add messages to and remove messages from each message queue. The configuration files specify log parameters, network parameters, memory settings, queue settings, and names of application-instance (for example, queue manager) configuration files. Examples of log parameters are logging type (linear or circular), log size, log buffers, and primary/secondary log allocation. Examples of network parameters are TCP keep-alives, and channel-connection settings. The queue settings specify the permitted length of each message queue, whether the messages on the queue should persist after a restart, how large each individual message can be, whether the queue is part of a cluster of queues, and whether an external application should be triggered to retrieve the message upon arrival to the queue. “User exits” are read-only, custom code such as code to provide security checking when an application requests to remove a message from a work queue. Other exits might be used to encrypt or compress messages. Some of the objects, such as a queue object that defines the queue, may be locked when “opened” for use by an external application.
An operator of the middleware program may change the configuration files as needed for proper operation of the middleware. It is prudent to occasionally backup the configuration files, queue objects, authorization tables and other files of the middleware program in case there is a system failure which deletes or corrupts them. It is not necessary to backup the basic middleware program code, because the basic code can be obtained, if needed, from a stagnant disk. In the case of a message-queuing middleware program, the messages on the queue are not generally backed up because they are too transient. External applications can backup and control such data, if desired. However, other types of data objects in other types of programs may be backed up. The backup of the configuration files, queue objects, authorization tables in IBM MQ Series/Websphere MQ program is currently performed as follows: An MQSeries application instance (for example, a queue manager) is stopped in order to release all locked files and provide for a consistent backup, which is then performed by an external backup program. Alternatively, the queue manager can be left running (and thus, needed repository files are locked in use), and a tool can be used to query the queue manager for settings that need to be saved. Such settings include objects, such as queues, channels, processes, and security objects. They also include the authorizations to those objects (such as the authorizations for an application to connect to a queue to contribute or retrieve a message). Each of these objects has authorizations (otherwise called permissions) that determine which ids and groups are permitted to access the object. The entire system, including the authorizations settings (which are not part of the objects themselves), was backed up by stopping the instance and relinquishing the lock. Then an “offline” filesystem backup was performed of all files in the repository. Most MQSeries installations keep repository files at the /var/mqm/qmgrs location on UNIX machines. The offline filesystem backup comprised the steps of 1) stopping external applications, and thus disconnecting their connections to MQSeries middleware, 2) stopping MQSeries middleware instances (queue managers), 3) an external storage program such as IBM Tivoli Storage Manager (TSM) is used to backup the /var/mqm and /var/mqm/log filesystems (which comprise the whole of MQSeries data files), 4) MQSeries is restarted, 5) external applications are restarted. The /var/mqm/ filesystem contains the repositories for each of the queue managers. This includes the objects and their associated permissions. That filesystem also contains message exits and all necessary configuration files. The /var/mqm/log filesystem was also backed up to provide recovery for the data in the queues. The whole filesystem was backed up, and users were then left to determine which files would be necessary to recover should a “restore” be needed.
One problem with a known backup process is that the middleware program is shut down during the backup. It is also known in other environments for a program which owns a lock to a repository to relinquish the lock to another program which needs to access the repository. However, for some programs such as IBM MQ Series/Websphere MQ program, the repository is essential to operation, and without the lock the proogram will be precluded from performing most tasks (until the lock is regained). Another problem was that even if a tool was used to backup the objects while the instance was running, the authorizations for those objects were not backed up (because they are stored separately) and thus the backup presented only a portion of the configuration settings necessary to completely recreate the instance.
A general object of the present invention is to facilitate the process of backing up a middleware program or other program.
Another object of the present invention is to permit backup of configuration files and other files of a middleware program or other program, without interfering with operation of the middleware program or other program.
Another object of the present invention is to facilitate backup of a comprehensive collection of information relating to the configuration of the queues.